This invention relates generally to forage harvesters and, in particular, to forage harvester row crop attachments.
Row crop attachments for forage harvesters typically include a plurality of row crop divider units arranged side-by-side on a base frame to define a plurality of crop conveying paths through which gathering chains pass. Rotary knives are provided adjacent an entrance of each conveying path for cutting off crop material before it is conveyed rearwardly through the conveying paths by the gathering chains. The gathering chains are disposed in an extended profile as shown in U.S. Pat. No. 4,397,134 to H. N. Lausch et al, or they are disposed in a non-extended profile as shown in U.S. Pat. No. 4,813,217 to R. Arnold. When the gathering chains are in the extended profile, they each wrap around a drive sprocket and two idler sprockets with one of the idler sprockets located in an extended position forwardly of the rotary knives. In the non-extended profile, the idler sprockets in the forwardly extended positions are eliminated so that each gathering chain wraps around a drive sprocket and only one idler sprocket. A drawback of the row crop attachments shown in the aforementioned Lausch et al and Arnold patents is that the gathering chains cannot be converted between extended and non-extended profiles.